• 한국양식학회:학술대회논문집
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• 한국양식학회 2006년도 수산관련학회 공동학술대회 발표요지집
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• pp.430-431
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• 2006

• 한국양식학회:학술대회논문집
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• 한국양식학회 2004년도 수산관련학회 공동학술대회 발표요지집
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• pp.401-402
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• 2004

• 한국동물학회:학술대회논문집
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• 한국동물학회 2001년도 공동 춘계학술대회
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• pp.60.2-60
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• 2001

No Abstract, See Full Text

• 한국동물학회:학술대회논문집
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• 한국동물학회 2001년도 공동 춘계학술대회
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• pp.61.1-61
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• 2001

No Abstract, See Full Text

• 한국패류학회지
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• 제31권4호
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• pp.267-272
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• 2015

This study was conducted in order to elucidate the dissemination mechanism of P. olseni using field and laboratory experiments. For this purpose, we quantified the level of P. olseni infection in buried (healthy) and surfaced (gapped) R. philippinarum from a clam bed on Wi-do Island on the west coast of Korea. In addition, the levels of internal and released P. olseni cells from artificially infected (and later dead) R. philippinarum were monitored for 8 days using the RFTM-2 M NaOH lysis method. Our results indicate that P. olseni cells in buried R. philippinarum was $2,655,625{\pm}1,536,936cells/clam$; the level in gapped R. philippinarum was considerably lower, $28,203{\pm}24,889cells/clam$ (p < 0.05). In the laboratory experiment, the P. olseni cells remained in the host tissue 2 days after death was approximately 50% lower than the level of infection measured in living clams. The level dropped to 20% 4 days after death and to 1.5% 6 days after death; eight days after death, P. olseni cells were undetectable since the R. philippinarum flesh had completely decomposed. The level of released cells on the day of death was only 0.05% of the internal level in live R. philippinarum; however, the level increased to 2.3% 5 days after death then gradually decreased and no released cells were detected 8 days after death. Therefore, our laboratory experiment suggest that the low level of P. olseni infection observed in gapped R. philippinarum at Wi-do Island could be caused by lysis of the most of P. olseni cells during the decomposition of dead R. philippinarum tissues. Until the end of decomposition of R. philippinarum, 6.68% of the total amount of P. olseni was released within 8 days. Our study showed that the amount of P. olseni cells from dead host is a considerably higher level than naturally released from healthy R. philippinarum, suggesting that death of the host plays an important role in the dissemination of P. olseni.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.252-253
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• 2003

바지락포자충 Perkinsus는 미국과 유럽 등지에서 굴과 바지락에 기생하며 고수온기숙주의 대량 폐사를 유발하는 원생동물로 이에 대한 연구가 활발하게 진행 중인 패류질병이다. Choi 와 Park (2001), Choi et at.(2002)은 우리나라 전 연안과 일본 Isahaya Bay에 서식하는 바지락에서 Perkinsus를 검출하고 이들의 감염도와 조직병리학적 특성을 보고한 바 있다. (중략)

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.503-504
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• 2000

바지락포자충 Perkinsus는 미국과 유럽 등지에서 굴과 바지락에 기생하며 고수온기 숙주의 대량 폐사를 유발하는 원생동물로 이에 대한 연구가 활발하게 진행중인 패류질병이다. Choi 와 Park (1997)은 1990년대 초반부터 나타난 여름철 바지락 대량 폐사 원인 중의 하나로 바지락포자충을 폐사 원인 생물로 추정한 바 있다. 이 연구는 1997년부터 진행중인 우리 나라 전 해역에 대한 바지락포자충 감염현장 조사의 일환으로, 경남지역에 분포하는 바지락의 바지락포자충 감염에 대한 조사 보고이다. (중략)

• Ocean and Polar Research
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• 제43권4호
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• pp.365-370
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• 2021

Manila clam Ruditapes philippinarum is present at high rates of density in tidal flats in Cheonsu Bay on the west coast of Korea, where clams often exhibit mass mortalities in late summer. We monitored the pathologic condition of clams at Hwangdo tidal flat (HD) to understand the parasitic impacts on clam fitness. Manila clams were fully ripe in July and spawned during August and September, as the histology indicated. The histology revealed that clams in HD tidal flats were heavily infected by the protozoa parasite Perkinsus olseni, as the monthly prevalence ranged from 53% (September) to 93% (August). In addition, Manila clams were co-infected by the metazoan parasite Cercaria tapetis and Parvatrema duboisi with the prevalence of 0-33% and 0-14%, respectively. Massive hemocyte infiltration and subsequent inflammation were commonly observed from the gills of P. olseni infected clams. Clusters of P. olseni trophozoites and heavy hemocyte infiltration were also observed from the female gonad, suggesting that P. olseni interferes with host gonad maturation. The larval trematode occupied almost the entire host gonad, resulting in gonad castration. In addition, Metacercaria of P. duboisi were observed from the subsurface of the mantle. Ray's fluid thioglycollate medium assay (RFTM) indicated that clams collected in August and September contained approximately 4.0×106 P. olseni cells/g gills. Condition Index (CI) declined gradually from spring to early summer, and the decline in CI was interpreted as a consequence of the heavy parasitism, as the parasites drain the host's net energy to be used in somatic growth and gamete production.

• Ocean and Polar Research
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• 제37권1호
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• pp.49-59
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• 2015

이 연구에서는 바지락의 성 성숙이 활발한 봄철에 경기만 선재도, 전북 곰소만, 및 남해 완도 등, 연중 수온 분포가 다른 지역에 분포하는 바지락 채집하여 P. olseni 감염이 번식에 미치는 영향을 조사하였다. 바지락의 산란은 연중 수온이 곰소나 선재도보다 높은 완도 바지락이 서해안 곰소 및 선재도 바지락보다 빠른 성 성숙 및 산란 활동을 보였다. P. olseni 감염이 바지락의 번식에 미치는 영향은 감염도가 다른 지역에 비해 세 배 이상 높은 완도에서 관찰되었으며, 완도 바지락은 여포 크기, 여포 내 성숙 난의 수 및 번식량 등이 타 지역보다 유의적으로 낮았다. 따라서 P. olseni 감염은 폐사 이외에도 다른 연구에서 밝혀진 바와 같이 번식 활동에 부정적인 영향을 미치는 것으로 확인되었다.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.388-388
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• 2003

Parasitic organisms in the Manila clam Ruditapes philippinarium were investigated from May 2001 to April 2002 from a population of clam inhabiting intertidal zone of Shi-Heung Ri on the west coast of Jeju. Perkinsus atlanticus and Cecaria tapidis were the two main parasites that occurred firequently among the clams. Occurrence of P atlanticus varied seasonally with lowest level in late September 2001 (6.0%) and highest infection level in March 2002 (86.0%). (omitted)